Patch lining has all the benefits of a drain liner but is often used as an isolated repair to a particular section of the drainage system rather than lining the whole length. Patch liner can be used to correct a fractured drain, repair an open joint or seal a root damaged pipe joint. This is a very quick method of repair with an average process time of around 3 hours from start to finish. The patch is fitted onto an inflatable packer which is inserted into the drain to the defective area. Once in place, the packer is inflated and the patch is set to the walls of the pipe, filling cracks and joints with resin. Once cured, the packer is removed from the drain, leaving the patch liner formed inside the pipe.